Initial commit

bundled/Crypto/Cipher/Utils.hs

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+module Crypto.Cipher.Utils
+    ( validateKeySize
+    ) where
+
+import Crypto.Error
+import Crypto.Cipher.Types
+
+import Data.ByteArray as BA
+
+validateKeySize :: (ByteArrayAccess key, Cipher cipher) => cipher -> key -> CryptoFailable key
+validateKeySize c k = if validKeyLength
+                      then CryptoPassed k
+                      else CryptoFailed CryptoError_KeySizeInvalid
+  where keyLength = BA.length k
+        validKeyLength = case cipherKeySize c of
+          KeySizeRange low high -> keyLength >= low && keyLength <= high
+          KeySizeEnum lengths -> keyLength `elem` lengths
+          KeySizeFixed s -> keyLength == s